水曲柳顺纹压缩率和PDR的变化规律研究  

Variations Between Longitudinal CompressiveRatio and PDR of Ash Wood

作　　者：张燕[1] 宋魁彦[1] 佟达[1] 

机构地区：[1]东北林业大学生物质材料科学与技术教育部重点实验室,哈尔滨150040

出　　处：《森林工程》2012年第6期1-3,共3页Forest Engineering

基　　金：国家自然科学基金(31070489)

摘　　要：利用木材弹塑性的特性对经过不同条件水热软化处理后水曲柳幼龄材和成熟材分别进行顺纹压缩,分析顺纹压缩率和PDR之间的关系和顺纹压缩过程中试材弹性恢复的状况,为后续的弯曲试验提供前期基础。结果表明:在沸水软化时间为140～150 min时,试材可以获得较好的顺纹压缩性能;顺纹压缩率和PDR呈正相关;顺纹压缩恢复过程可以分为弹性、弹塑性和塑性3个阶段,弹性阶段瞬时即可恢复,弹塑性阶段较缓慢地恢复,塑性阶段不再恢复,出现永久的塑性变形。On the basis of wood elastic-plastic properties,the juvenile and mature ash wood after hydrothermal treatment in different conditions were longitudinal compressed,and the relationship between longitudinal compressive ratio and PDR and the compressive rebounding properties during longitudinal compression were analyzed.This study can provide a basis for the following bending process.Results showed that samples had better longitudinal compression performance on the condition of 140~150 min softening in hot water.The longitudinal compressive ratio was increased with the increase of PDR.Longitudinal compressive rebounding procedure was separated into three phases,namely elastic,plastic-elastic,and plastic phase.The deformation was rebounded instantaneously in elastic phase,while being rebounded slowly in plastic-elastic phase.In plastic phase,the deformation was not rebounded any more and a permanent deformation was formed.

关 键 词：水热处理 顺纹压缩 PDR 压缩恢复率 

分 类 号：S781.23[农业科学—木材科学与技术]